It is important for large sporting events, in particular for soccer games, that the fields are vacuumed shortly before the start of a game, because heavy rains can have the result that the playing fields, which are in an open stadium, become flooded and the drains installed in the field are no longer able to absorb the water and thus the field has standing water, at least in some locations. Soccer games are often played regardless of the conditions, which means they are often not played under normal playing conditions. It can be very expensive for an organizing club to postpone a game shortly before its start, or to stop a game after it had started and deal with angry spectators.
A basic purpose of the present invention is therefore to prepare a field of grass in such a manner so that soccer games or other events can be played under any type of weather conditions on the field, and that moreover at the same time a careful maintenance of the sensitive grass becomes possible.